The Role of Cookies and Sessions in State Management

A typical HTTP request-response cycle is stateless, meaning the server treats each incoming request as independent and unrelated to previous ones. This stateless nature allows the server to handle large requests efficiently, improving scalability. However, many real-world applications require the server to remember user interactions, making state management essential.

Why does state management matter?

Consider the following examples:

• A newsfeed application, when users log in, they expect personalized content, saved preferences, and a seamless experience across page reloads. Without state management, refreshing the page would log them out, and their feed would reset.

• Similarly, in a video streaming service, users rely on watch history, recommendations, and saved progress to persist across sessions.

To address these challenges, cookies and sessions help maintain user state, ensuring a consistent and secure experience across different interactions. Whether it’s a newsfeed, a streaming platform, or a chat application, managing user data effectively is key to delivering a smooth user experience.

In the following sections, we’ll explore cookies and sessions in detail.

Cookies

Cookies are small data stored on the user’s device by the browser. The data stored in the cookies is labeled with a unique ID. They are sent to the server with each request and can be used for various purposes, including:

• Session management: Cookies can be used for session management. By exchanging cookies, the website recognizes users and their preferences, such as whether a specific user likes to see news related to sports or politics.

• Personalization: Cookies help the server maintain client-specific information, which helps provide an experience tailored to a particular user. Cookies can also be used to save users’ browsing history and activity, personalizing the user’s experience on a website or application. ...